Assessing the oral health of an ageing population: methods, challenges and predictors of survey participation

To examine predictors of participation and to describe the methodological considerations of conducting a two-stage population-based oral health survey.

An observational, cross-sectional survey (telephone interview and clinical oral examination) of community-dwelling adults aged 45-64 and ≥65 living in Nova Scotia, Canada was conducted.

The survey response rate was 21% for the interview and 13.5% for the examination. A total of 1141 participants completed one or both components of the survey. Both age groups had higher levels of education than the target population; the age 45-64 sample also had a higher proportion of females and lower levels of employment than the target population. Completers (participants who completed interview and examination) were compared with partial completers (who completed only the interview), and stepwise logistic regression was performed to examine predictors of completion. Identified predictors were as follows: not working, post-secondary education and frequent dental visits.

Recruitment, communications and logistics present challenges in conducting a province-wide survey. Identification of employment, education and dental visit frequency as predictors of survey participation provide insight into possible non-response bias and suggest potential for underestimation of oral disease prevalence in this and similar surveys. This potential must be considered in analysis and in future recruitment strategies.